Gyroscopic control system for dirigible craft



Oct. 6, 1931. w; rr 1,826,013

GYROSCOPIC CONTROL SYSTEM FOR DIRIGIBLE CRAFT Filed Aug. 18 1930 2 Sheets Sheet 1 66 12 .1 J O f 1 y &

1 W/lM 4, WWW

Oct. 6, 1931. Y w. MEREDITH 1,826,013

GYROSCOPIC CONTROL SYSTEM FOR DIRIGIBLE CRAFT Filed Aug. 18 1930 2 Sheets-Sheet 2 menu a. 6, 193-1 PATENT- OFFICE rnnnnnrcx 'wxnnmu MEREDITH, or rnnmionooen, ENGLAND" GYBOSCOPIG con'rnon SYSTEM non DIBIGIIBLE cream Application'llled August 18,1930, s mi 11o.47e,1o7, and in Great Britain m 18, 1925.

This invention relates to automatic control systems for aeroplanes aridjlike. dirigible craft. I

It has'been.

t scope having a horizontal axis 0 spin for controlling the rudder and to employ a] second gyroscope'having avertical axis of spin for controlling the elevators and the ailerons:

ent invention a single gyroscope comprising arotor possessing three axes of freedom and haying the rotor axis arranged in the fore and aft direction of an aeroplane is employed to control aerodynamically both the steering and the pitching movements of the aeroplane.

According to another feature of the invention a single universally mounted gyroscope is arranged so that one gimbal ring controls the rudder or the steering movements of an aeroplane and the other gimbal ring controls the elevators or the pitching movements of the aeroplane. According to an-' other feature of the invention a single uni n versally mounted gyroscope is associated between the azimuth ring'and the gyroscope frame and a follow-up system for controlllng a 'servomotor for operating the rudder, andwith means sensitive to relative movement between the pitch ring and the gyroscope ,frame and a follow-up system'for controlling a scrvomotor for operatingthe elevators, the

whole arrangement'bei ng ada ted to control proposed to emplo a gyro;

According to one feature of the present with means sensitive to relative movementmotor to make the angular displacement of the rudder, proportional or approximately so 3 to the azimuthal disturbance of the aeroplane the lateralmotion of the aeroplane generally consists of an oscillation, and the degree'of damping of this oscillation is of importance and within limits may be increased by the operation ofailerons.

' The present invention has for an object to provide a method of damping the lateral mo- 6 tion due to application of rudder angle by an azimuthgyroscope associated with followup mechanism apart from the operation of ailerons. y According to one feature of the present invention, ina gyroscopic system wherein an azimuth gyroscope is associated with a ser- Vomotor and follow-up gear as aforesaid, the damping of the lateral motion is improved'by applying rudder Eangle determined by the displacement in roll of the aeroplane relative 'to a free gyroscope rotor axis. The rudder angle is caused to be the-sum of two parts, one part being determined by the angle through which the aeroplane has'turned ea its course and the other being determined by the angle to which .the aeroplane is banked.

Figuresl and 2 are respectively an eleva v tion and a plan of a universally mounted gyroscope for controlling both the steeringand the pitching mo'ver'nentsof-an aeroplane, and

Figure 3 is an elevation showing a modification in which the rotor axis is tilted. v

- As shown in Figures 1 and 2, the gyroscope comprises a rotor 1 having its axis of spin 2-2 arranged horizontally in the'fore-andaft direction of the aeroplane 3 and'meunted in an inner gimbalring or pitch ring 4.- The pitch ring 4. has itsaxis of pitch 55 arranged horizontally-athwartship of the aero-' plane and mounted in an outer gimbal ring or azimuth ring 6.. The azimuth ring6 has its axisof orientation 7 7 arrang d 5 tically and mounted in a frame 8. P

The rotor is driven by compressed air nozzles-(not shown) to which compressed air is supplied through the lower Kflmm'on; mounting of the azimuth ring 6, at any 10( other suitable driving means may be employed.

The gyroscope is used to control the rudder of the aeroplane by coupling the azimuth ring by means of a link 9 to a sensitive piston valve 10 controlling a compressed air'inlet port 11 and outlet ports 12,13 in a casing 14 fast on the frame 8. The inlet and outlet .ports communicate by flexible conduits 15, 16 with the respective ends of a servoinotor cylinder 17 fast on the aeroplane and containing a double acting piston. The piston rod 18 of the servomotor is connected to the rudder control cables 19, 20 for operating the rudder. 21 are guide pulleys. In the operation of the arrangement, relative movement in azimutl1 between the azimuth ring and the frame causes the valve 10 to open one end of its scrvomotor cylinder to the compressed air supply and the other e d toexhaust so as to'apply rudder angle. 11 order to obtain a follow-up efi'ectfin which the movement of the rudder is proportional to the displacement ofthe azimuth ring, the frame 8 carrying the casing is pivotally mounted on the aeroplane and is connected to the piston rod 18 by a link 22.

The gyroscope is used to control the elevators by coupling the pitch ring by means of a link 24 to a sensitive piston valve 25 controlling a compressed air inlet port 26 and outlet ports 27, 28 in. a casing 29 slidably mountedon the frame 8. The outlet ports communicate by means of flexible conduits 3,0, 31 with the respective ends of a servomotor cylinder 32 fast on the aeroplane3 and containing a double acting piston. The piston rod 33 of this servomotor is connected to the elevator control cables 34, 35 for operating the elevators. 36 are guide pulleys. In the operation of the arrangement, relative movement between the pitch ring and the frame causes the valve 25 to open one end of the servomotor cylinder 32 to compressed air and the other end to exhaust, so as to apply'elevator angle. In order to obtain a follow-up effect, in which the movement of the elevators is proportional to thedisplacement of the spitch rlng, the casing 29' is slidably mounted in vertical guides 37 on the frame 8 and is connected to the piston rod 33 by Bowden wire or the like mechanism 38, 39. y

' The control system according to the in- "vention is particularly intended to be applied to an aeroplane which may be flown without aileron control.

In the arrangement shown in Figures 1 and 2 rolling movement of the aeroplane about its longitudinal axis would result in the pitch ring rotating about the rotor'axis and there will be no movementbetween the pitch ring and the azimuth ring or between the azimuth ring and the frame 8.

In the arrangement shown in Figure 3 the pitch ring is tilted so that the axisv of spin 2-2 of the rotor is tilted with respect to' the, longitudinal axis] of the aeroplane 02-0: which is also the line of flight. In other respects the arrangement shown in Figure 3 is similar to that shown-in Figures 1 and 2. The effect of tilting the axis of spin of the rotor is as follows: 1 If the aeroplane rolls about its longitudinal axis H, that is, if the aeroplane banks, the resulting movement of the rotor axis cannot be accommodated entirely by rotation of the pitch ring about the rotor axis but is accommodated partly by such rotation and partly by rotation of the azimuth ring about its axis of orientation. The azimuth ring will thus be turned relatively to the frame and will bring the servomotor 17 into action through the agency of the piston valve 10. The sorvomotor'will thus apply the rudder. The effect of this application of the rudder when the aeroplane banks is to increase the lateral stability provided that the aeroplane .18 so constructed that side-slip produces a stable rolling moment. Thus in the arrangement shown in Figure 3 the movement of the servomotor and the rudder is proportional to the relative movement 'between the azimuth ring and the frame 8 which in turn is the sum of two parts, one being determined by the angle though which the. aeroplane has turned off its course and the other part being determined by the angle to which the aero plane is banked. To determine the amount of movement of the azimuth ring due to the aeroplane rolling, the rotation of the rotor axis about the line of flight may be resolved into a component aboutthe rotor axis which has-no effect on the control of the aeroplane and a component about the azimuth axis.

In both the modifications *illustrated any convenient anti-topple. mechanism may be provided for countering the inherent tendenlcy of the gyroscope to precess. As shown, the anti-topple mechanism comprises a piston valve 40 mounted on the azimuth. ring and in communication with a source of compressed air through the lower, tiunnion hearing of the azimuth ring. The piston 41 of the valveis connected by a link 42 to the pitch ring. Opposite ends of the valve are connected by conduits 43, 44'to opposite ends of s 'a small air motor 45 which is mounted on the azimuth ring. The piston rod 46 of the servo- -motor is connected by a link 47 to the frame 8. When the pitch-ring moves relatively to the azimuth ring it moves the valve piston 41 so as to lace one end of the servomotor 45 under pre ure and open the otheriend to exhaust. 'Theservomotor then applies a torque to the azimuth ring so as to cause the v pitch ring to move towards its normal position, as shown in- Figure 1 or in Figure 3. The servomotor 45 is asmall motor relatively to the servomotors 13 and32 so that it can only rotate the pitch rin g'slowly. The servomotor 45 thus-will not materially affect movement of the pitch ring relatively to the azi-- muth frame when the aeroplane alters its angle of climb and thus will not prevent the pitch ring from applying the elevator to correct the alteration in the angle of climb. 'lhe servomotor is, however, large enough to deal with the slow precessionsarising from frierotation of theearth.

tion of the bearings in the ing an azimuth gyroscope'having its axis of spin arranged in the direction of the length of the craft but inclined to the longitudinal axis of the craft in a substantially vertical plane, a

. servomotor for actuating the rudder of the craft in accordance with relative turning movement of the longitudinal axis of the craft and. the axis of spin about an erect axis, and a second servomotor for actuating the elevator 'planeiof the craft'in accordance with relative turning movement of the longitudinal axis of the craft and the axis of spin about a transverse axis.

v 2. A gyroscopic control system for a dirigible craft moving in a fluid medium comprising an azimuth gyroscope having its axls of spin arranged in the direction of the length of the craft, a servomotor for actuating the rudder of the craft in accordance with rela tive turning movement of the longitudinal axis of the craft and the axis of spin about an verect axis, and anti-topple mechanism for maintaining the axis of spin inclined backr Wardly to the longitudinal axis of the craft;

3. A gyroscopic'control system for' a diri- ,gible craft -moving in a fluid medium, comrisin a rotor an inner 'mbal rin whereon the rotor is mounted to spin, an outer gimbal ring whereon theiiiner gimbal ring is mounted to turn, aframe wheregn-the outer gimbal ring is mountedto turn about an erect axis, a servomotor for actuating the rudder, 'a-control'device for the servomotor 'operatively connected to the frame and outer ring and actuated 15y relative turning movement between said parts, and anti-topple mechanism for maintaining the plane of the gimbal ring int'lined backwardly about a transverse axis relatively to the' plane containing the longitudinal and horizontal trans,

verse axes of the craft.

4. A gyroscopie control system for a dirigible craft moving in a fluid medium, com- .7 prisinga rotor, an inner gimba-l ring whereon gyrosco pe and the 1 rotor the rotoris mounted to spin about an axis extending in the direction of the length of the craft, an outer gimbal ring whereon the innor ring is mounted to turn about a transverse axis, a frame-whereon the out er ring is mounted to turn'about an erect axis, a servomotor for actuatin the rudder of the craft, a control device or the servomotor actuated by relative movement between the outer ring and the frame, a second servomotor and a control device for the secondservomotor actuated by relative movement between the inner and outer rmgs.

5. A gyroscopic control system-for a diri- 'glble'craft moving in a fluid medium, com.-

prising a rotor, an inner gimbal ring whereon the rotor is mounted'to spin about an axis extending in the direction of the length of the craft, an outer gimbal ring whereon the inner ring is mounted to turn about a transverse axis, a frame whereon the outer ring is mounted to turn about an erect axis, a servomotor for actuatingthe rudder of the craft, a difl'crential control mechanism for the servomotor operatively connected to the outer ring and to V the frame for-actuation by relative movement of said parts and operatively connectedto the servomotor for actuation thereby, a second servomotor for actuating the elevator, a differential control mechanism for the second servomotor operatively connected to the in-- ner and outer rings for actuating by relative movement of said parts and operatively con- Eected to the servomotor for actuation there A gyroscopic control system for a-dirigible craft moving in afluid medium, comprising a rotor,an-in ner gimbal'ring whereon the rotor'is mounted to spin about an axis extending in the direction" of the length of the craft, an outer gimbal ring whereon the inner ring is mounted to turnabout a transverse axis, a frame whereon the oriter ring is mounted to turn about an erect=axis, a servomotor for actuating the rudder of the craft, a differential control mechanism for the servomotor operatively connected. to the outer-ring and to the frame for a-ctuation,by relative movement of said parts and operatively connected toAshe servomotor for actuation thereby, and an anti-topple mechanism operatively connected to the inner and outer rings to restore the axis of spin of'the rotor to' a predetermined tilted position with respect to the longitudinal axis of the craft.

7. A gyroscopic control system for a 'dirigible craft moving a fluid medium, comprising a rotor, a universal mounting for the reby the rotor supported to rotate norma llyabout an axis fixed in the craft and extending in the direction of the length of the craft but inclined to the longitudinal axis of the craft in a substantially vertical plane, a device for actuating the rudder of the craft, an operatiye connectionbetween said said device and the rotor by which the rotor brings said second device into action when its axis of rotation turns relatively to the fixed axis about an axis transvei-se to the length of the craft. 7

8. A gyrescopic control system for a di-rigible craft moving in a fluid medium, comprising a single rotor, a universal mounting on which the rotor is supported-to spin normally about a fixed axis extending in the direction of the length of the craft but inclined to'the longitudinal axis of the craft in a substantially vertical plane, a detecting device for detecting turning movement of the axis of the spin of the rotor relative to the fixed axis about an erect axis, a relay mechanism for actuating the rudder of the craft, an operative connection between the detecting device and the relay mechanism by which the former controls the operation of the latter in accordance with the nature of said turn ing movement, a second detecting device for detecting turning movement of the axis of the spin of the rotor relative to the, fixed axis abouta transverse axis and a second relay mechanism for actuating the elevator of the craft and an operative connection between the second detecting device and the second relay mechanism by which said device controls the operation of said mechanism in accordance with the nature of said turning movement.

9. As gyroscopic control system for a dir-,

igible 'craft moving in a iiuld medium, comprising a singlerotor, a umversal mounting wheneon the rotor is mounted to spm normally about an axis fixed in the craft, and

extending 'in the direction of the length of the craft, but-inclined to the longitudinal axis of the craft in a substantially vertical plane, mechanism for measuring turning movement of the axis of spin of the rotor rel-- ativeto two defined axes in 'the craft, a servomotor for actuating the rudder of the craft a second servomotor for actuating the elevator of the craft, an operative connection between the measuring mechanism-and the first servomotor by which the former 'controls the operation of the latter in ,accordance with the relative turning movement of the rotor axis about one of the defined axes, and an operative connection between the measuring mechnism and the second servomotor by which the former controls the operation of the latter in accordance with the relative turning movement of. the rotor axis about the other defined axis.

10. A gyroscopic control system for a dirigible craft moving in a fluid medium, comprising a servomotor for actuating the rudder, a control device for bringing the servomotor into action to apply the rudder, a gyroscopic rotor, a universal mounting on which the rotor is mounted tospin normally about an axis fixed in, and extending in the direction of length of thecraft but inclined to the longitudinal axis of the craft in a substantially vertical plane, an operative connection between the rotor and the control device by whichthe former actuates the latter to bring the'servomotor into action in accordance with the turning movement of the rotor axis relative to the fixed axis about an erect axis, an operative connection between the servomotor and its control device by which the servomotor restores the control device to normal, a second servomotor for actuating the elevator of the craft, a second control device for bllIiQ'lllfl' the second servomotor into action to adjust the elevator,

an operative connection between the rotor and the second control device by which the former actuates the latter to bring the second servomotor into action in accordance .with turning movement of the rotor axis relrection of the length of the craft but inclined to the longitudinal axis of the craft in a substantially vertical plane, a relay mechanism for'controlling the rudder of the craft, a second relay mechanism for controlling the elevator of the craft, an operative connection "between one relay mechanism and one gimbal ring whereby the relay mechanism is controlled by the movement of said ring and an'operative connection between the other relay mechanism and tlie other gimbal ring wherebv'the latter relay mechanism is controlled by the latter gimbal ring.

12. A gvroscopic control system for a dirlgible. craft moving in a fluid-medium, comby which the rotor is universally mounted with its axis of spin extending in the direction of the length of the craft but incline to the longitudinal axis of'the craft in a substantially vertical plane, a rudder actuating member, a reversible servomotor for driving said member, two control elementsmovable' relatively to one another to determine whether, and in which dlrectlon the servomotor wlll drive sald member, anoperative -prising a gyroscopic rotor, two gimbal rings I connection between one of the control ele- I ments and one gimbal ring by which m ve-' ment of said ring is -1 1npa rted to the con rol.

element, an operative connection between one proportional said of the control elcments'and the'rudder actuthe azimuthring;

- l In testimony wh ating member by whichthe movement of the latter is imparted tothe former, an elevator actuating member, a second reversible servomotor for driving the elevator actuating member, .two other icontrol elements movable relatively to' one another to determine ereof I have signed my.

'tur'ning movement of name to this specification.

WILL

, FREDERICK" 7 whether, and in'whi'ch direction, the servo motor 18 to drive the elevator actuatmg-mem- 1 her an operative connectlon between one of said latter control elements and the other of the said control elcmentsand an operative connection between one of said latter control elements and the elevator actuating member by which movement 'ofsaid member is ima parted to said control element.-

13. A gyroscopiccontrol s'ystemforadin .igible craft moving ina fluid-medium, c'omprising a rotor a universal mounting by which the rotoris supported to spin normally I about an axis extending in the direction of f length of the craft but inclined to the longitudinal axis of the craft in asubstan'tially.

vertical plane so that the forward end of the vaxis of spin'is higherwith'respect to said longitudinal-axisthan is the rearward end of the axis of spin, a rudder actuating mem- 1 her, a servomotor for driving said member,

" a control devicefor the servomotor, anoper- -ati've".connection between the control device 7 turns relativel and rotor for bringing thecontrol device into action when the axis of s in of the rotor to the era about erect axis in the on t. i

14. A gyroscopic control system for a dirigible craft moving in a fluid. medium com- I prising a rotor, an inner gimbal rin' m which the rotor is mounted, with its ax s of spin normally extending in a vertical fore and aft plane of the craft, an azimuthnng in which the inner ringis mounted to turn and inner rings and tending to maintain-the inner ring tilted about its axis relatively to the said erect axis so that the fore end of the axis of sp n of the rotor is uppermost, a device for etecting turning movement of the azimuth ring relatively to the frame about said erect axis, a rudder actuating member, a servomotor, a control device operable by said detecting device to bring the servomotor into action to drive said member in accordance. with the directions of said turning movement, a devi'cefor measuring the movement' of therudder actuating member and operable to cause the control device to put the servomotor out of action when the movement of the rudder actuating movement is liao 

